Self-centering log feed for barkremoving machines



Dec. 10, 1957 R: E. ANNIS, JR., EI'AL 2,315,776 SELF-CENTERING LOG FEEDFOR BARK-REMOVING MACHINES Filed Dec. 21, 1954 4 Sheets-Sheet 1' Dec.10, 1957 R. E. ANNIS', JR., EFAL 2,815,776 7 SELF-CENTERING LOG FEED FORBARK-REMOVING MACHINES Filed Dec. 21, 1954 4 Sheets-Sheet 2 Dec. 10,1957 R. E. ANNIS, JR., ETAL SELF-CENTERING LOG FEED FOR BARK-REMOVINGMACHINES 4 Sheets-Sheet 3 Filed Dec. 21, 1954 Dec. 10, 1957 R. E.ANNISQJRW ETAL 2,815,776

- SELF-(ENTERING LOG FEED FOR BARK-REMOVING MACHINES Filed Dec. 21, 1954=4 Sheets-Sheet 4 SELF-CENTERING LOG FEED FOR BARK- REMOVING MACHINESRupert E. Annis, J12, Nashna, N. H., and Douglas A.

Philhrook, Rumford, Maine, assignors to Improved Machinery line, Nashua,N. H., a corporation of Maine Application December 21, 1954, Serial No.476,642

4 Claims. (Cl. 144 208) This invention relates to a machine for removingbark from logs, particularly from logs of relatively short length such,for example, as pulpwood logs.

Barking machines of the type having a plurality of bark-removing toolsmounted in an annular rotating member through which a log i fed axiallywithout rotation are known to the art and have proved entirely practicalwhere saw logs of relatively long length are to be barked. In regions,such as Northeastern United States, however, logs cut for use in makingpulp are quite short, commonly about four feet in length, and with suchshort logs the heretofore known barking machines could not operatesuccessfully, principally due to the inability of theirfeed mechanismsproperly to support without rotation a short log while feeding itthrough the annular rotating toolcarrying member where it was operatedupon by the barkremoving tools.

Accordingly, it is an object of the present invention to provide abarking machine having a novel feed mechanism capable of handling logsof much shorter length than has heretofore been the case.

It is a particular feature of the bathing machine of the presentinvention that it is self-opening, that is, each entering log to bebarked itself successively opens the feeding elements and bark-removingelements of the machine in accordance with the diameter of thatparticular log. Hence, the barking machine of the invention iscompletely automatic in operation and need only be kept supplied withlogs to be barked.

For the purpose of more fully explaining the barking machine of theinvention, reference is now made to the following description of apreferred embodiment thereof, together with the accompanying drawings,in which:

Fig. 1 is a side elevation of the barking machine of the invention,certain parts being broken away;

Fig. 2 is a fragmentary and enlarged vertical longitudinal sectionalview showing generally the feeding and bark-removing elements of themachine of Fig. 1;

Fig. 3 is a vertical transverse sectional view on the line 33 of Fig. 1and shows a portion of the feeding mechanism not shown in Fig. 2;

Fig. 4 is an enlarged transverse vertical sectional view of one of thefeeding mechanisms as shown in Fig. 2, taken on the line 44 of Fig. 1;

.Fig. 5 is an enlarged fragmentary end elevation of the bark-removingmechanism of the machine of Fig. 1;

Fig. 6 is an enlarged longitudinal sectional view of a portion of thebark-removing mechanism and is taken on the line 6-6 of Fig. 5;

Fig. 7 is a plan view of the machine of Fig. 1 showing the power-drivenmeans thereof; and

Fig. 8 is a fragmentary and enlarged vertical longitudinal section ofthat portion of the feeding mechanism not shown in Fig. 2.

Referring to the drawings and particularly to Figure 1 thereof, thebarking machine according to the present invention includes a frame 10upon which the various elements are mounted. Said frame may be arrangedwith fixed supports as shown, or may be mounted on suitable nited StatesPatent 0 wheels, the latter being particularly desirable since itenables the use of the machine at the source of the logs, which, amongother things, eliminates the handling of bark removed from the logs.

-In general, the major elements of the barking machine consist of abark-removing mechanism (generally designated 12) mounted midway alongframe 10, and a pair of feeding mechanisms mounted at either sidethereof for moving a log axially through the bark-removing mechanism, afront feeding mechanism (generally designated 14) closely adjacent thebark-removing mechanism 12 at the forward side thereof and a rearfeeding mechanism (generally designated 16) closely adjacent thebarkremoving mechanism 12 at the rear side thereof. Preferably, asupplemental pusher feeding mechanism (generally designated 18) ismounted on frame 10 in advance of front feeding mechanism 14 to aid infeeding logs to the bark-removing mechanism 12.

The bark-removing mechanism, as best shown in Figs. 5 and 6 includes adrum-like element 20 rotat'ably supported by suitable bearings 22 on astationary tube 24 which is itself mounted on frame 10. On drum 20 arerotatably mounted six shafts 26 spaced at equal distances from thecentral axis of the drum element and from each other and with their axesgenerally parallel to said central axis. Each of said shafts supports abark-removing tool 30 for swinging movement toward and away from thecentral axis of drum 20, torsion springs 28 being interposed betweeneach of said shafts 26 and drum 20 to urge said tools toward saidcentral axis to remove the bark from a log being passed axiallytherethrough generally along said central axis. The working pressure ofthe torsion springs 28 may be adjusted by an adjusting screw 34interposed between a torsion-spring-adjusting arm 36 and drum 20. Theleading edge of the bark-removing tools 3th is slanted inwardly andrearwardly in the direction of log advance as shown by the arrows in thedrawings, and is of a somewhat bowed shape departing at an angle ofabout 30 to 60 degrees to the tangent of a log in a direction againstthe relative movement of log and tool, to provide a scraping edgesurface on the tool tip. Thus when the forward end of the log to bebarked is moved against the tool edge and the drum 20 which carries thebark-removing members 30 is rotated in a direction counterclockwise inFig. 5, the tool will be swung outwardly away from the central axisagainst the force of its spring 28, and said spring will maintain thetip of the tool 30 in contact with the log to scrape the bark therefrom.The tips of the tools 30 may extend for but a short distance axially ofdrum 20 and may be suitably spaced so that their total scraping area maybe utilized to provide rapid bark removal, each tool tip traveling in agenerally helical path around the advancing log adjoining said paths ofthe other tool tips. To prevent the tips of the tools from contactingeach other when no log is in the bark removing mechanism, the tools areprovided with arms 32 which contact a stop 38 on the drum 20corresponding to a desired minimum distance of the tool tips from oneanother.

The front and rear log-feeding mechanisms, together with thesupplemental feeding mechanism associated therewith, co-operate topresent a log to, and centrally advance a log through, the rotatingbark-removing mechanism while supporting it substantially on the centralaxis of said mechanism and preventing rotation of the log, so that thebark-removing tools will operate most effectively since thebark-removing mechanism itself provides very little log support.Furthermore, this necessary supporting function is provided even withrelatively short logs, since the novel feed mechanism hereinafterdescribed need extend for but a short axial distance adequately tosupport a log in cantilever and also may be placed closely adjacent thebark-removing tools, both front and rear. Thus, by using such feedmechanism both in front of and behind the bark-removing mechanism andspaced closely thereto, logs as short as the separation between thesupporting elements of said feed members will be adequately supported incantilever to be operated upon by tools 30 and such log will bepresented, supported, and held on the central axis of said mechanismirrespective of the diameter of the log.

The two log-feeding mechanisms being nearly identical, the forward oneonly of such mechanisms will herein be described in detail, and themodifications of the rear mechanism later pointed out. The forwardlog-feeding mechanism as shown best in Fig. 4, with Fig. 2 additionallyproviding a vertical central longitudinal sectional view thereof, inessence is a novel three-jaw self-centering chuck. The lower jaw of saidchuck comprises a transversely extending beam 40 mounted below thecentral axis of drum and having a vertical post 42 mounted thereongenerally centrally thereof and extending downwardly through a suitablebearing 44 in frame 10 to permit vertical movement of beam 40 toward andaway from the central axis. A pair of coil tension springs 46 areprovided, one at each end of beam 40, extending upwardly between saidbeam and frame 10 of the machine to urge said beam yieldably upwardlytoward the central axis.

For advancing a log, power-driven means are provided on beam 46, saidmeans including a plurality of spur rolls 48, preferably three in numberwith their axes perpendicular to the central axis and spaced therealongto provide an adequate log support in cantilever. The spur rolls 43 aremounted in suitable bearings 50 midway along beam 40 and are driven bymeans hereinafter described to advance a log through the feed mechanismand present it to the bark-removing mechanism.

A pair of upper jaws comprising the other two jaws of the three-jawchuck are each mounted to cooperate with the lower jaw to support a log.Each of such jaws comprises a lever 52 which has rotatably mounted atits upper inner free end in suitable bearings 54 a plurality of spurrolls 56 axially spaced for aiding the lower spur rolls 48 in supportinga log along the central axis without rotation, its other end beingmounted on an end of beam 40 by a suitable pivot pin 58. Midway betweenits ends, lever 52 is supported by a fixed pivot shaft 60 mounted onframe 10. Thus, by such interconnecting lever, the upper jaw spur rolls56 will be moved toward and away from the central axis in synchronismwith the lower jaw spur rolls 48, and will similarly be urged towardsaid central axis by springs 46.

In order that the jaws may be opened automatically by an oncoming log,the upper jaws are each provided with a forwardly and outwardlyextending cam surface 62, such surface extending forwardly on the innerand upper ends of levers 52 at an angle of about to the central axis andextending forwardly and outwardly for a distance great enough to beactuated by the largest diameter log which the machine is intended todebark. A guide roll 64 of hourglass configuration is positioned infront of lower-jaw spur rolls 48 to guide logs generally centrally ofsaid spur rolls.

The lower jaw of the forward feeding mechanism is preferably providedwith supplemental means 18 for feeding a log to spur rolls 48 inalinement therewith. Such means, as best shown in Figs. 1, 3, and 8,comprises a pivotally mounted pusher conveyor mounted at one end of thelower jaw for vertical movement therewith. Thus an extension frame 75)is mounted on main frame 10 extending forwardly thereof. The extensionframe 70 has mounted at its forwardmost end for pivotal movement aboutshaft 72 a swinging frame 74 of longitudinally concave cross sectionwhich has a slot 88 extending centrally of its upper surface, whichlatter frame is mounted at itsrear end: on stub shafts 76 on beam 40'for vertical movement therewith. The. swinging frame 74 has mountedtherein forward and rear pairs of chain conveyor sprockets 78 and 80having a pair of endless chains 82 passed thereabout. Preferably twopusher dogs 34 are mounted on said chains for pivotal movement abouttheir centers and each is supported in an upright position extendingthrough slot 38 by a plate 86 which extends beneath the upper flight ofchains 82 from the forward sprocket 78 to just short of the rearsprockets 80, the upright pusher dog being pivoted backward by the log,as it moves around sprocket 80. The guide roll 64 is preferably mountedon swinging frame 74 between rear sprockets 80 and forward spur rolls48.

The rear feed mechanism is identical to the above described mechanismexcept in the provision on its lower jaw of a downwardly and forwardlyslanted surface having an additional power feed roll 66 thereon to aidin receiving somewhat crooked logs from the bark-removing mechanism andpassing them to output chute 68.

The various elements of the barking machine of the invention are alldriven (Fig. 7) by a single electric motor 90 mounted on frame 10 at therear end thereof, although a gasoline or Diesel engine may be used aswell. Thus the drum 20 is driven on its outer surface by a plurality ofV belts 92 driven from main shaft 94. The forward and rear lower jawspur rolls 48 and 66 and the guide roll 64 are driven through suitableshafting from sprockets 96 mounted on main frame 10 and spaced from saidspur rolls and guide roll to allow vertical movement thereof, and therear conveyor sprocket 80 is driven from guide roll 64 by a suitablechain drive 98. Clutches may be provided for the various elements asdesired.

In operation, a log placed on the concave upper surface of swingingframe 74 is moved toward the jaws of the forward feeding mechanism bypusher dog 84. As the advancing end of the log comes into contact withthe cam surfaces 62 on upper jaw levers 52, the jaws are opened and theleading end of the log is engaged by lower jaw spur rolls 48 and is fedto the bark-removing mechanism while being supported in cantilever. Thecontact of the leading end of the log with the leading edges of thebark-removing tools 30 opens said tools until their tips contact theouter surface of the log, whereupon the bark is scraped from the outersurface of the log as it passes through the bark-removing mechanism, thebarkremoving tools 30, by reason of springs 23, being pressed inwardlyagainst the surface of the log so that the bark will be removedtherefrom even though the log has flat or even concave portions. Therear feeding mechanism picks up the leading end of the log in the samemanner as does the front, and supports the trailing end of the log incantilever as it passes from the front feeding mechanism. The log, itsbark removed, finally passes to outlet chute 68. As soon as a log clearsthe front feeding mechanism, a succeeding log may be fed into it, thepusher dogs 84 being spaced at distances that automatically preventoverfeeding, that is, the advancing of a succeeding log before apreceding log has cleared the front feeding mechanism.

It will be appreciated by those skilled in this art that variousmodifications may be made within the purview of the invention and thescope of the appended claims.

We claim:

1. A barking machine comprising bark-removing means including aplurality of bark-removinn tools mounted for movement toward and awayfrom a central axis to remove bark from a log being fed axiallytherethrough, and log-feed means for presenting a log to saidbark-removing means, said feed means including a self-centering chuckhaving a lower jaw positioned below said central axis and mounted forvertical movement toward and away therefrom along a path perpendicularthereto, an upper jaw mounted substantially in said path of said lowerjaw for swinging movement toward and away from said central axissubstantially along said path, and having thereon a cam surfaceengageable by an oncoming log to open said jaw, lever means for movingsaid lower and upper jaws in substantial synchronism to support a logsubstantially on said central axis and means normally urging said jawstoward said central axis.

2. A barking machine comprising bark-removing means including aplurality of bark-removing tools mounted for movement toward and awayfrom a central axis to remove bark from a log being fed axiallytherethrough, and log-feed means for presenting a log to saidbarkremoving means, said feed means including a self-centering three-jawchuck having a lower jaw positioned below said central axis and mountedfor vertical movement toward and away therefrom and having power-drivenroll means thereon for advancing a log through said feed means, a pairof upper jaws each mounted for swinging movement toward and away fromsaid central axis about a fixed pivotal axis parallel to said centralaxis, and having a cam surface engageable by an oncoming log to opensaid jaw, lever means interconnecting said upper and lower jaws formoving said jaws in substantial synchronism to support a logsubstantially on said central axis, and spring means normally urgingsaid jaws toward said central axis.

3. A barking machine comprising a frame; bark-removing means including arotatable drum mounted on said frame, and a plurality of bark-removingtools mounted in said drum for swinging movement toward and away fromthe central axis thereof; and log-feed means for axially presenting alog to said bark-removing tools while preventing rotation thereof, saidfeed means including a self-centering three-jaw chuck mounted on saidframe and having a lower jaw and a pair of upper jaws, said lower jawbeing positioned below said central axis for vertical movement towardand away therefrom and having a power-driven roll thereon for advancinga log through said feed means, each of said upper jaws being mounted forswinging movement toward and away from said central axis and having acam surface engageable by an oncoming log to open said jaw, a pair oflever means interconnecting said upper and lower jaws for moving saidjaws in substantial synchronism to support a log substantially on saidcentral axis, each of said lever means being mounted on said frame forswinging movement about a fixed pivotal axis parallel to said centralaxis and having its lower end pivotally connected to said lower jaw andits upper end connected to said upper jaw, and spring means extendingbetween said lower jaw and said frame to urge said lower jaw upwardlyand thus urge said jaws toward said central axis.

4. A barking machine comprising bark-removing means including aplurality of bark-removing tools mounted for movement toward and awayfrom a central axis to remove bark from a log being fed axiallytherethrough, and log-feed means for presenting a log to saidbarkremoving means, said feed means including a self-centering chuckhaving a lower jaw positioned below said central axis and mounted forvertical movement toward and away therefrom along a path perpendicularthereto, an upper jaw mounted substantially in said path of said lowerjaw for swinging movement toward and away from said central axissubstantially along said path, and having thereon a cam surfaceengageable by an oncoming log to open said jaw, interconnecting meanslinking said jaws for movement in substantial synchronism to support alog substantially on said central axis, and means normally urging saidjaws toward said central axis.

References Cited in the file of this patent UNITED STATES PATENTS1,957,792 McManis May 8, 1934 2,646,092 Kolpe et a1. July 21, 19532,655,961 McComb Oct. 20, 1953 FOREIGN PATENTS 67,469 Sweden June 4,1929 1,070,548 France Feb. 24, 1954

